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Ontario Running Weather

Sunday, July 26, 2026 · Hour-by-hour forecast updated 5:10 PM PDT

Best Time to Run in Ontario Today

5 AM–6 AM

66°F and clear at peak. Wind 2 mph from the ENE, dew point 56°F.

83
Peak FitScore
Temperature
66°F / feels 67°
Wind
2 mph ENE, gusts 2
Dew Point
56°F — noticeable
Humidity
69%
UV Index
0 — Low
Air Quality
68 AQI — Moderate

Hourly running conditions

☁️ 5 PM
45
93° feels 90° 12 mph W 1% rain
🌤️ 6 PM
38
92° feels 89° 12 mph W 1% rain
☀️ 7 PM
46
89° feels 86° 12 mph W 1% rain
🌙 8 PM
47
83° feels 81° 10 mph W 1% rain
🌙 9 PM
45
79° feels 78° 10 mph W 1% rain
🌙 10 PM
46
76° feels 79° 1 mph NW 1% rain
🌙 5 AM
80
67° feels 67° 4 mph NE
🌅 6 AM
83
66° feels 67° 2 mph ENE
☀️ 7 AM
70
69° feels 72° 2 mph ENE
☀️ 8 AM
58
75° feels 78° 1 mph SE
☀️ 9 AM
51
81° feels 83° 2 mph SSW
☀️ 10 AM
47
86° feels 89° 4 mph SW
80–100 Excellent 60–79 Good 40–59 Fair Below 40 Poor

7-day running forecast

☁️
Today Jul 26
95° / 69°
83
🏃 5 AM–6 AM
Mon Jul 27
96° / 66°
83
🏃 5 AM–6 AM
☁️
Tue Jul 28
95° / 63°
79
🏃 6–9 AM
☀️
Wed Jul 29
95° / 75°
67
🏃 6–9 AM
☁️
Thu Jul 30
96° / 74°
68
🏃 6–9 AM
☁️
Fri Jul 31
97° / 75°
65
🏃 6–9 AM
☁️
Sat Aug 1
100° / 79°
58
🏃 6–9 AM
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Running Forecast
iMessage
🌤 Tomorrow in Ontario: Best window: 9–11 AM (FitScore 95) 6am: 48°F, feels 45° — NW 8mph 9am: 58°F, feels 56° — W 12mph 12pm: 66°F, feels 65° — SW 8mph ☔ Rain likely after 3pm.
Yesterday 8:14 PM Nightly

Ontario running weather FAQ

What's the best time to run in Ontario today?

Based on today's FitScore analysis, the best time to run is 5 AM–6 AM with a peak FitScore of 83/100. Check the hourly breakdown above for detailed conditions throughout the day.

What months are best for running in Ontario?

The best months for running in Ontario are June, July, August, September. The most challenging months are typically November, December. Mild summers with low humidity make for ideal running. Watch for marine layer fog in coastal areas.

What is the FitScore?

FitScore rates each hour from 0–100 for outdoor exercise based on temperature, humidity, dew point, wind, precipitation probability, UV index, and air quality. Higher scores mean better conditions.

Nearby:Pomona, CAFontana, CACorona, CA
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